3D printing of casting pattern leads the industrial transformation in Ningxia

There are more than 26 thousands casting companies in China, accounting for half of all the global manufacturers of casting products. But the traditional method of handmaking castings is heavily reliant on human resources and energy, and can produce a lot of environmental pollution.

But thanks to the spread of 3D printing technology, a revolution is taking place in the industrial casting industry in Ningxia Hui autonomous region.

3D printing machine [File photo: VCG]

Liu Yi can still remember the terrible working conditions at the foundry where he landed his first job after graduation. The air in the factory was full of dust and the sweat, and the high temperatures made people feel dull and sleepy.

These type of working conditions seem like a world away from the air-conditioned workshop at Kocel Intelligent Machinery. Liu Yi's old factory has been transformed with the introduction of 3D printing technology, which has increased the productivity of the factory five-fold, and reduced the burden of manual labor on the workforce.

Liu Yi, now the vice president of The National Intelligent Foundry Industry Innovation Center in Ningxia, has seen for himself the huge changes that have taken place in China's casting industry.

"Traditionally it was time consuming to make a single casting product. A sand core needs to be created. It usually takes 1 to 2 months to make the pattern. By using 3D printing, the cast is now made using a digital mold, which generally only takes 2 or 3 days to make. The process is very quick; and the sand core can be printed in 1 to 2 hours."

Kocel Intelligent Machinery is located in the national economic and technological development zone in Yinchuan. The company owns 12 3D sand core printers. When the printer starts, the sand box slides into the printer, and the sand is spreading evenly across the base.

Nozzles then spray resin onto the layers of sand, gluing the sand together. The process is repeated until a three dimensional sand core is formed. The key responsibility of the workers in this intelligent foundry is to keep an eye on the smooth running of the 3D printers, and supervise the automated transportation of the completed products around the factory. The intelligent production line has cut the number of people involved in the production process from 35 down to 7.

3D printers have several advantages over the older production methods. The sand cores can be produced more quickly and with a high degree of accuracy, which makes it easier and faster to make changes to the design. The printers in this foundry were developed by Xu Yunlong and his team, and were the first use of 3D printing technology in China for making sand cores.

Xuyunlong, who is the vice president of Kocel Institute of Intelligent Machinery Research, spent 7 years developing the first printer.

"Different kinds of sand have different structures when you look at them under a microscope. They will perform differently during the printing process, which changes the patterns of each layer of printing, which in turn affects the accuracy of the printing. So we spent a lot of time testing the performance of the printers."

5 engineers in Xu's team spent 4 years testing and fine-tuning the new printing technology. It is their goal to develop the world's largest 3D sand core printer, and set the international standards for the technology.

This mission is shared by the National Intelligent Foundry Industry Innovation Center in Ningxia.

Mai Xinfu, the chief economist of the Ningxia Municipal commission of economy and information technology, says the support that industry receives from the innovation center has contributed a lot to the development of the industry in Ningxia.

"Traditional industries form a large part of Ningxia's GDP. To reduce industry pollution in the region and shift towards a green economy, our industrial transformation is very important. This is our economic task in future."

Investment in the industrial restructure of Ningxia reached 43 billion yuan in 2017, which is about 6.2 billion U.S. dollars. This is an increase of 15 percent compared to last year. And the total investment in industrial technology innovation made up 34 percent of all industrial investment in 2017.

Liuyi says that the traditional casting process will gradually be replaced with the new methods of casting using 3D printers.

"At present, 3D printing products make up around 20 percent of our total production. We hope that by the year 2020, almost 80 percent of our production will be produced using 3D printing."

Around 20 thousand tons of mouldings and 10 thousand tons of precision products are produced using the new 3D printing technology each year. The result has been a boom in the economy of Ningxia.